Bioreduction activated prodrugs of camptothecin: molecular design, synthesis, activation mechanism and hypoxia selective cytotoxicity
作者:Zhouen Zhang、Kazuhito Tanabe、Hiroshi Hatta、Sei-ichi Nishimoto
DOI:10.1039/b502813b
日期:——
Several water-soluble derivatives (CPT3, CPT3a–d) of camptothecin (CPT) were synthesized, among which CPT3 bearing an N,N′-dimethyl-1-aminoethylcarbamate side-chain was further conjugated with reductively eliminating structural units of indolequinone, 4-nitrobenzyl alcohol and 4-nitrofuryl alcohol to produce novel prodrugs of camptothecin (CPT4–6). All CPT derivatives were of lower cytotoxicity than their parent compound of CPT. In contrast, CPT4 and CPT6 showed higher hypoxia selectivity of cytotoxicity towards tumor cells than CPT. A mechanism by which a representative prodrug CPT4 is activated in the presence of DT-diaphorase to release CPT was also discussed. The bioreduction activated CPT prodrugs including CPT4 and CPT6 are identified to be promising for application to the hypoxia targeting tumor chemotherapy.
合成了几种水溶性喜树碱衍生物(CPT3、CPT3a-d),其中带有N,N′-二甲基-1-氨基乙基氨基甲酸酯侧链的CPT3进一步与吲哚醌、4-硝基苄醇和4-硝基糠醇的可还原消除结构单元偶联,产生了新的喜树碱前药(CPT4-6)。所有CPT衍生物的细胞毒性都低于其母体化合物CPT。相比之下,CPT4和CPT6对肿瘤细胞的缺氧选择性细胞毒性高于CPT。还讨论了一种代表性前药CPT4在存在DT-二氢酶的条件下释放CPT的激活机制。包括CPT4和CPT6在内的生物还原激活的CPT前药被认为有望应用于靶向缺氧肿瘤的化疗。